I'm using the "dark reader" firefox extension, and I had forgotten that this forum doesn't have a dark theme :) Thoroughly recommend it to anyone with a strong aversion to bright screens like me.
I'm Nuclear (in the demoscene: Nuclear/The Lab, Nuclear/Mindlapse, and Codeninja/MLFC). I started programming in BASIC on a ZX Spectrum when I was a kid, and later moved first to Turbo Pascal, and then C/C++ and assembly under MS-DOS in the mid/late 90s.
I never was very much into consoles, preferring PC games, so unconventionally my interest in the GBA did not start from a gaming perspective. When I found out about the wonderful little ARM device in 2003-2004 and about the availability of flash cartridges for it, I bought one (a black GBA SP which I still have and use today) expressly for the purpose of programming it, together with a flash2advance cartridge.
My main interest in the GBA initially was to make demos for it, which I never ended up doing (maybe one day). Instead I wrote a few standalone effects, released a thin abstraction library which I called "libgba", later renamed to "gbasys", and which I don't use any more, and wrote a now very dated guide for setting up a build environment for the GBA.
Eventually I also played a couple games on the GBA, mostly Irridion2 and Doom, but most often just my old original GameBoy tetris cartridge.
As much as I enjoy GBA programming, I didn't end up finishing many projects on it. I made a Magic the Gathering life counter which I used extensively myself while playing magic, and a simple classic-style tetris game to avoid having to carry the bulky original tetris cartridge with me (I don't like any of the more modern tetris variants I tried).